If a fault occurs in a device or the like, a fault point is specified and fault repair work is performed by a worker. For example, as disclosed in Patent Literature 1, there is known a technique for using Augmented Reality (hereinafter, AR) to simplify a removal operation for a paper jam in a copying machine. Specifically, when a paper sheet is not detected by a predetermined sensor within a predetermined time, it is assumed that a paper jam has occurred, and a video of the inside of the copying machine, which has been previously prepared corresponding to a paper jam occurrence position, and an operation procedure are displayed in a superimposed manner. Thereby, a paper jam occurrence point in the copying machine can be easily recognized, and guidance for the removal operation can be easily provided. It should be noted that the AR is a technique for displaying data managed in a computer (hereinafter, computer graphics image data), such as characters, figures, still images or moving images, into a real environment in a superimposed manner to give supplementary information.